Explanation of Ubuntu Hard Drive Wear and Tear

Thank you for finding a solution to save our hard drives , I hope this will be fixed in next ubuntu

Two quick questions: (1) does this affect desktops too? or only laptops w/ power saving turned on? wasn't clear from your post... (2) how do you make the fix permanent? I'm not that familiar with the commandline to know whether or not your solution gets wiped out everytime you reboot...

Have you considered, why does it spin up so often ?
With laptops, if there is no user activity, is it really important to wake up writing to disk ?
I know there are daemons running around and file atimes have to be updated and file systems have to be synced, but has anyone sat down and thought, if they are really important for laptop users ? Or could we for example put the noatime option as default, suspend some daemons and increase the interval of writing dirty buffers to disk, when there is no user activity?

I read that the solution is to set the APM to 255, meaning that no power management used at all.
But what is the default value set by Ubuntu if somehow i want to revert back ?

maybe it doesn't work for all drives?

$ sudo hdparm -B255 /dev/sda

/dev/sda:
setting Advanced Power Management level to disabled
HDIO_DRIVE_CMD failed: Input/output error

It's true... and I reported a "strain" of this bug at the beginning of September just as Gutsy was being run through final tests. No one has ever changed the status on the bug-ticket, neither has anything more been said about it. I noticed it on my Dell notebook, and reported the findings immediately...

Bug-report can be found here:
https://bugs.launchpad.net/ubuntu/+bug/137420

It most definitely needs a more solid solution. On a notebook you hear it going on and off constantly and you can just sit and count all those spin-up spin-down cycles winding towards your hard drives ultimate destruction. Hmm.

Is this issue truly limited to just Ubuntu? What about other flavors like Fedora, Slackware or Suse? If it has been claimed that it's a BIOS/firmware related issue, and there is significant evidence to back it, maybe you should clean up the article -- or at least the title.

Honestly, I read this article because it mentioned an issue regarding Ubuntu. Since it's been DUGG, you'll probably get a number of readers that have no idea where the issue stems from, but they sure remember reading that this particular flavor of Linux has a problem. Validated or not.

Are you attempting to provoke thought, or scare away potential converts?

Very useful, thanks.

I imagine I am harder on my laptops than a lot of people, and I tend to by real cheap ones as well, but 2.5 years sounds like a great life time for a laptop drive based on my experience. That said, I've only been running Ubuntu for a few months now, and it was Windows 2K-XP before that, so I am going to to waaaaay out on a limb and claim that at least Windows does something similar. In fact, I would lay good money on the harsh setting when the laptop is unplugged.

Coming from another angle, you will find that it is difficult at best to get drive life specs from laptop vendors, but battery life is usually right near the top of all the marketing bullet points. So, laptop and OS vendors have a mutual interest in beating on the drives in favor of power consumption since not only does long battery life help sell more of their product from a marketing standpoint, but dead drives help sell them from a product replacement standpoint. Most of the laptop users I know will replace the whole thing if the drive dies since they don't even know it can be replaced.

Anyway, I think the harshest setting makes complete sense when unplugged, especially considering the lower risk of damage due to impact, but all that Ubuntu is missing in this case is a modification of this parameter, and several others like it, when the laptop is plugged in. Windows has had this feature set for years, and it should be trivial for Ubuntu/Linux folks to add it to the existing battery/power monitoring utility. Heck, for all I know, it is already in there. Anyone have the fu to check that?

I have seen this behaviour on all Dell laptops we have bought recently (Latitude D630/D830), and it is present in Windows XP as well. A fix is to add sth. like

/dev/sda {
apm 254
}

to /etc/hdparm.conf and to add a startup link with

sudo ln -s /etc/init.d/hdparm /etc/rcS.d/S07hdparm


I have an Apple Macbook Pro and I upgraded the drive to 160gb "Momentus Seagate" drive.
Now I can hear a noise like the heads parking every few mins, I have checked the OSX power setting and disabled the option to shut down the drives when possible but still i hear the noise.

After reading this I would like to check my drive. Could I check this with the SMARTmon tools on a mac, in VMware running XP for example?

Y'know, it'd be less offensive to call anonymous users "AnonymousCoward" if it was actually possible for people to put their real name in when submitting a comment. All I've got are subject and comment boxes, no box for the name.

The situation is somewhat less clear than you might think from the article, but the basic takeaway message is that Ubuntu doesn't touch your hard drive power management settings by default. In almost all cases, it's more likely to be your BIOS or the firmware on your hard drive.

The script that's executed when you plug or unplug your laptop is /etc/acpi/power.sh. The relevant sections are:

function laptop_mode_enable {
...
$HDPARM -S $SPINDOWN_TIME /dev/$drive 2>/dev/null
$HDPARM -B 1 /dev/$drive 2>/dev/null
}

That is, when the laptop_mode_enable function is called, we set the drive power parameters. Now, by default laptop_mode_enable isn't called:

if [ x$ENABLE_LAPTOP_MODE = xtrue ]; then
(sleep 5 && laptop_mode_enable)&
fi

because ENABLE_LAPTOP_MODE is false in the default install (check /etc/default/acpi-support). This means that, by default, we do not alter the hard drive power settings. In other words, the APM settings that your drive is using in Ubuntu are the ones that your BIOS programmed into it when the computer started. This is supported by the fact that people see this issue after resuming from suspend. We don't touch the hard drive settings at that point, so the only way it can occur is if your BIOS or drive default to this behaviour.

If you enable laptop mode, then we will enable aggressive power management on the drive and that may lead to some reduction in hard drive lifespan. That's a fairly inevitable consequence of laptop mode, since it only makes sense if the laptop enages in aggressive power management. But, as I said, that's not the default behaviour of Ubuntu.

There's certainly an argument that we should work around BIOSes, but in general our assumption has been that your hardware manufacturer has a better idea what your computer is capable of than we do. If a laptop manufacturer configures your drive to save power at the cost of life expectancy, then that's probably something you should ask your laptop manufacturer about.

I've never heard of heads in a hard drive referred to as "sliders".

Sorry if anyone has been trying to post a comment and have been unable to.  This site is pretty new, and I hadn't installed the keys for reCaptcha yet.  I've fixed the problem.

Thanks for all the comments on digg.com! 

brian

aka

root

What if your drives are connected via raid controller and presented as a LUN? Does this bug still affect your drives?